Original
A texture from the game "Unreal" has been as an example of a game texture. I did not have access to the original data, but instead obtained it ' second hand' from here . This may have undergone conversion between several formats, since it only has a limited number of colours (approx 170), however I don't really think this is going to be too critical to these tests.
The uncompressed original image would occupy either 512kb at 16bpp, or
768kb at 24bpp.
Compression Results:
Equal Resolution (512x512)
8 Bit palettised Size: 256k (+ 0.75k table) RMS error: 0.0 (not surprising ... see above) |
4 Bit palettised Size: 128k (+ 0.05k table) RMS error: 17.1 |
DXTC Size: 128k RMS Error: 13.5 |
2x2 VQ Size: 64k (+ 2k table) RMS Error: 16.4 |
Equal Storage Space (approx 64k)
This shows the equivalent image in 24bit, 8bit, DXTC, and VQ.
Basic 24 bpp texture Initial Resolution: 148x148 RMS Error: 47.5 |
8 Bit palettised Initial Resolution: 256x256 RMS Error: 48.2 |
DXT1 Initial Resolution: 364x364 RMS Error: 49.2 |
2x2 VQ Resolution: 512x512 RMS Error: 16.4 |